Details
Riftia pachyptila
The giant tube worm forms dense colonies at deep-sea hydrothermal vents. It has no mouth or gut and depends on internal bacteria for nutrition.
Map: Ecoregions 2017 © RESOLVE (CC BY 4.0) · Natural Earth (PD)
It lives around Pacific deep-sea hydrothermal vents. Colonies grow where sulfide-rich vent fluid mixes with oxygenated seawater.
Tube length 50-240 cm; weight 100 g-1.5 kg. A red plume extends from a hard white tube, and hemoglobin-rich blood carries both oxygen and sulfide. The body remains protected inside the tube.
Cathemeral in the lightless deep sea, it lives in dense colonies. The plume gathers dissolved chemicals and withdraws quickly when disturbed.
Its diet is unlike ordinary feeding: symbiotic bacteria use hydrogen sulfide to make organic compounds. The worm absorbs that nutrition instead of eating with a mouth.
Adults release eggs and sperm into the water. Larvae disperse to new vents and establish bacterial symbiosis after settlement.
It is listed as Least Concern, but vent habitats naturally appear and disappear with geological activity. Deep-sea mining could add local disturbance.
